1. Field of the Invention
The present invention relates to a gear puller, and more particularly to a gear puller having two assemble models and multiple paws to pull a circular element and convenient in use.
2. Description of Related Art
A gear puller as shown in FIG. 7 is used to pull a circular element (70), such as a gear, a sleeve, a bearing or the like to detach the circular element (70) from a shaft (71). The circular element (70) has an external surface, a center and a through hole. The through hole is formed at the center of the circular element (70). The shaft (71) is set in the center of the circular element (70) and has a distal end. A conventional gear puller (60) substantially comprises a screw shaft (61), a connecting seat (62), four cranks (63) and two paws (64).
The screw shaft (61) selectively abuts against the distal end of the shaft (71) and has a proximal end, a distal end, an external surface, an external thread, a hexagonal head (611) and a tip (612). The external thread is formed on the external surface of the screw shaft (61). The hexagonal head (611) is formed on the proximal end and can be rotated by a wrench. The tip (612) is formed on the distal end of the screw shaft (61) and selectively abuts against the distal end of the shaft (71).
The connecting seat (62) is connected rotatably to the screw shaft (61) and has a center, a threaded hole and two ends. The threaded hole is formed in the center of the connecting seat (62) and is screwed with the screw shaft (61).
The cranks (63) are mounted with the connecting seat (62) and each has a front end and a rear end. The front ends of two cranks (63) are pivotally and respectively connected to the ends of the connecting seat (62) with pivots (80) (80 is not found in the drawing).
The paws (64) are pivotally connected to the cranks (63) and each has a proximal end, a distal end and two hooks (641). The hooks (641) are formed on the front end and the rear end of the paw (64), respectively and have different directions.
In use, rotating the screw shaft (61) to make the tip (612) contact with the distal end of the shaft (71), and the paws (64) are pivotally rotated to make the hooks (641) on the front ends grip onto the circular element (70) at a side opposite to the tip (612). Then, rotating the hexagonal head (611) of the screw shaft (61) to push against the distal end of the shaft (71) with the tip (612), such that the circular element (70) can be separated from the shaft (71).
Defects and shortcomings of the conventional gear puller (60) are listed as follows:
1. The gear puller (60) only has two paws (64) to hold the circular element (70) and are not replaceable. Therefore, the conventional gear puller (60) can not be applied to different condition and is not versatile in use. The user must prepare multiple kinds of gear pullers (60) to fit with different conditions, and this is costly.
2. When the gear puller (60) is in use, the user must hold both the paws (64) with one hand and rotate the screw shaft (61) with the other hand. Therefore, the conventional gear puller (60) is not convenient in operation.